Implantable medical devices, such as electrical stimulators or therapeutic agent delivery devices, may be used to deliver electrical stimulation therapy to patients to treat a variety of symptoms or conditions such as chronic pain, tremor, Parkinson's disease, epilepsy, urinary or fecal incontinence, sexual dysfunction, obesity, mood disorders (e.g., depression), other psychiatric disorders (e.g., obsessive-compulsive disorder), gastroparesis or diabetes. In some cases, the electrical stimulation may be used to stimulate muscles, e.g., provide functional electrical stimulation (FES) to promote muscle movement or prevent atrophy. A patient may have more than one implantable medical device implanted to alleviate the variety of symptoms.
Generally, a clinician, e.g., physician, uses an external programming device to communicate with an implantable medical device. The clinician may use the external programming device to, for example, program the therapy delivered by the implantable medical device, or retrieve physiological or diagnostic information collected by the implantable medical device. Furthermore, a patient may use an external programming device to communicate with his or her implantable medical device, e.g., for control of therapy or to receive physiological or diagnostic messages.
External programming devices communicate with implantable medical devices transcutaneously using, for example, radio frequency of near-field magnetic communication techniques. Typically, external programming devices have been coupled by a cable to a telemetry head comprising an antenna for communication with implantable medical devices. The telemetry head is positioned over or very near the implantable medical device, with the cable enabling the programming device to be used a comfortable distance from the patient.